There is a massive fucking difference between raising concerns about the practical applications of inclusion of trans people and calling them deranged and perverted.
I agree. Just because you have a valid concern about how some malevolent males might exploit self-ID, that doesn't mean that you are not being transphobic when you make blanket sweeping negative assumptions and generalisations about an entire group, their motives, their thought processes, or deliberately misrepresent them.
I've thought for a while now that the term "gender critical" being used to denote the opposition of trans rights is the equivalent of those who were against extending gay rights calling themselves "bump-on-the-head critical".
Equivalent in the sense that when people say they are gender critical they mean they are gender stereotypes critical. So they are implying that trans people, all trans people are only trans because they realised they like this or don't like that stereotypical thing. Something that they don't actually know is the cause of gender or body disphoria.
Just like those who argue against same-sex rights calling themselves bump-on-the-head critical are similarly implying that all gay people are only gay because they received a bump on the head.
I would similarly think it reasonable to call it homophobic if some of the same rhetoric and misrepresentations that are used against trans-campaigners were to be used against gay rights campaigners. Talks of them wanting to "erase" marriage, "colonise" marriage, just because they want the term extended to include them. Endlessly misrepresenting them as attacking and abusing heterosexuals when it was homophobes (as they saw it) that were getting it in the neck. Heterosexuals per se were getting no bother.